JP7048566B2 - undercover - Google Patents

Description

The present invention relates to an undercover.

Generally, the vehicle is provided with exhaust system parts (catalyst, exhaust pipe, silencer, etc.) from the engine room of the vehicle body to the rear portion of the vehicle body through the lower portion of the vehicle body. These exhaust system parts are generally cylindrical, and are arranged in a recess in which the bottom surface of the vehicle body is recessed toward the passenger compartment to prevent the vehicle body from protruding downward. However, since the recesses protrude into the vehicle interior, there is a problem of narrowing the vehicle interior space.

For example, Patent Document 1 discloses a pipe element for an exhaust gas system of an internal combustion engine in which a plurality of rectangular pipe channels are arranged side by side by providing a plurality of side walls between a base wall and a cover wall. There is. In such a pipe element, since the exhaust flow path is composed of a plurality of pipe channels arranged side by side, the vehicle interior space can be narrowed as compared with the case where the exhaust flow path is composed of one cylindrical component. It is thought to be suppressed.

Japanese Patent Publication No. 2008-516130

However, the pipe element described in Patent Document 1 is still attached to the lower part of the vehicle body so as to project downward from the vehicle body. Therefore, it is desired that even if the exhaust system parts are provided in the lower part of the vehicle body, it is possible to suppress the protrusion to the lower part of the vehicle body.

Therefore, an object of the present invention is to make it possible to provide an exhaust system component in the lower part of the vehicle body without narrowing the vehicle interior space and without projecting downward from the vehicle body.

(1) The undercover according to the present invention is an undercover (for example, the undercover 1 described later) provided so as to cover the bottom surface of the vehicle body (for example, the vehicle body 2 described later), and is an upstream end (for example, described later). A cylindrical inflow port (for example, an inflow port 11 described later) arranged at the upstream end 1a) and allowing exhaust gas from an internal combustion engine (for example, an internal combustion engine 3 described later) to flow in, and a rear portion of the vehicle body (for example, described later). Between the exhaust port (for example, the exhaust port 12 described later) arranged at the downstream end corresponding to the rear portion 2b) (for example, the downstream end 1b described later) and having a flat and wide opening, and the inflow port and the exhaust port. It has an exhaust flow path portion (for example, an exhaust flow path portion 13 described later) that is connected and extends in a flat plate shape over a region corresponding to the vehicle interior.

According to (1) above, the undercover functions as an exhaust system component, and the exhaust flow path from the inflow port to the exhaust port is flat, so even if the undercover is attached to the bottom surface of the vehicle body, the passenger compartment space Does not narrow. In addition, since the undercover does not overhang the bottom of the vehicle body, it is possible to lower the vehicle height.

(2) In the undercover described in (1), the undercover is a resin product, and the exhaust after being discharged from the internal combustion engine and recovering exhaust heat flows in from the inflow port. May be good.
According to (2) above, the weight of the undercover can be reduced by using a resin product for the undercover that allows the low-temperature exhaust gas after the exhaust heat is recovered to flow in from the inlet, and the weight of the lower part of the vehicle body can be reduced. It is possible to improve fuel efficiency and steering stability.

(3) In the undercover according to (1) or (2), the upper edge portion of the exhaust port (for example, the upper edge portion 12a described later) is inclined diagonally upward as it goes backward from the exhaust port. It may have an inclined extension portion (for example, an inclined extension portion 14 described later).

According to (3) above, the exhaust gas that has passed through the exhaust flow path portion spreads diagonally upward immediately after being discharged from the exhaust port, so that the air on the bottom surface side of the vehicle body is vigorously accelerated backward to the bottom surface side of the vehicle body. It is possible to generate a downforce that attracts the vehicle body to the ground by the ground effect.

(4) In the undercover described in (3), a plurality of straightening vanes (for example, a straightening vane 15 described below) for partitioning the exhaust port in the width direction on the lower surface (for example, the lower surface 14a described later) of the inclined extending portion. ) May have.

According to the above (4), since the flow of the exhaust gas flowing out from the exhaust port is regulated by the straightening vane, downforce can be generated more effectively.

(5) In the undercover described in (4), two of the plurality of straightening vanes may be arranged at both ends in the width direction of the exhaust port.

According to the above (5), since it is possible to prevent the inflow of air from the side to the exhaust port, it is possible to enhance the rectifying effect of the exhaust by the rectifying plate.

According to the present invention, the exhaust system parts can be provided in the lower part of the vehicle body without narrowing the vehicle interior space and without projecting downward from the vehicle body.

It is a perspective view which looked at the vehicle provided with the undercover which concerns on one Embodiment of this invention from the bottom surface side. It is a perspective view which looked at the undercover which concerns on one Embodiment of this invention from the bottom surface side. It is a perspective view which looked at the undercover which concerns on one Embodiment of this invention from the downstream end side. It is a vertical sectional view of the undercover which concerns on one Embodiment of this invention. It is sectional drawing which follows the AA line in the undercover in FIG. It is a figure which looked at the undercover in FIG. 4 from the B direction. It is a figure which shows an example of the structure which the undercover is connected to the internal combustion engine which has an exhaust heat recovery structure.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a perspective view of a vehicle provided with an undercover according to an embodiment of the present invention as viewed from the bottom surface side. FIG. 2 is a perspective view of the undercover according to the embodiment of the present invention as viewed from the bottom surface side. FIG. 3 is a perspective view of the undercover according to the embodiment of the present invention as viewed from the downstream end side. FIG. 4 is a vertical sectional view of the undercover according to the embodiment of the present invention. FIG. 5 is a cross-sectional view taken along the line AA of the undercover in FIG. FIG. 6 is a view of the undercover in FIG. 4 as viewed from the B direction.

As shown in FIG. 1, the undercover 1 of the present embodiment is attached to the bottom surface of a vehicle body 2 having an internal combustion engine (hereinafter referred to as an engine) (hereinafter referred to as an engine) (not shown). Specifically, the bottom surface of the vehicle body 2 is configured to be a flat surface by being covered with a plurality of undercovers 21. The undercover 1 of the present embodiment covers the center of the bottom surface of the vehicle body 2 in the width direction from the engine room arranged in the front portion 2a of the vehicle body 2 to the rear portion 2b of the vehicle body 2, and is abbreviated as a plurality of undercovers 21. It is attached so that it is flush with each other.

The undercover 1 functions as an exhaust system component (exhaust undercover) that exhausts exhaust gas from the engine to the rear through the bottom surface of the vehicle body 2. That is, the undercover 1 has an inflow port 11 for inflowing exhaust gas from the engine at the upstream end 1a along the flow of exhaust gas, and has an exhaust port 12 at the downstream end 1b corresponding to the rear portion of the vehicle body 2. The inflow port 11 and the exhaust port 12 are connected by an exhaust flow path portion 13 extending in a flat plate shape.

The inflow port 11 is formed in a cylindrical shape, and the purified exhaust gas flows in through, for example, an exhaust gas purification device of an engine. In the undercover 1, the internal space 10 on the downstream side of the inflow port 11 is immediately formed into a horizontally long flat and wide shape by being crushed from the upper part to the lower part, and is an internal space of the flat plate-shaped exhaust flow path portion 13. It is continuous with 10.

As shown in FIG. 1, the exhaust flow path portion 13 extends in a flat plate shape over the entire length including the region 20 corresponding to the vehicle interior of the vehicle body 2. Specifically, as shown in FIG. 5, the exhaust flow path portion 13 includes a pair of flat plate strip-shaped upper surface plates 13a and lower surface plates 13b extending in the front-rear direction of the vehicle body 2, and a pair of side surface plates 13c and 13c. It has a horizontally long flat and wide internal space 10 which is formed in a flat plate shape and has the same shape over the entire length.

As described above, since the exhaust flow path portion 13 of the undercover 1 extends in a flat plate shape over the region 20 corresponding to the vehicle interior, the bottom surface of the vehicle body 2 is directed toward the vehicle interior side in order to attach the undercover 1. There is no need to dent it. Therefore, even if the undercover 1 is attached to the bottom surface of the vehicle body 2, the vehicle interior space is not narrowed and the undercover 1 does not project below the vehicle body 2.

The exhaust port 12 opens at the downstream end 1b of the undercover 1 in a horizontally long, flat and wide shape that is the same as the internal space 10 of the exhaust flow path portion 13. Therefore, the exhaust gas from the engine that has flowed in from the inflow port 11 flows downstream through the horizontally long flat and wide internal space 10 of the exhaust flow path portion 13, and then the exhaust port 12 that also opens in the horizontally long flat and wide shape. Is discharged to the rear of the vehicle body 2.

The upper edge portion 12a of the exhaust port 12 has an inclined extending portion 14 that is inclined diagonally upward as it goes backward (downstream) from the exhaust port 12. As shown in FIG. 1, the inclined extending portion 14 is arranged on the bottom surface of the rear portion 2b of the vehicle body 2, and extends diagonally upward along the bottom surface shape of the rear portion 2b of the vehicle body 2 starting from the exhaust port 12. .. Therefore, the exhaust gas that has passed through the exhaust flow path portion 13 spreads diagonally upward immediately after being exhausted from the exhaust port 12, adds air on the bottom surface side of the vehicle body 2, and accelerates vigorously backward. As a result, the undercover 1 makes the bottom surface side of the vehicle body 2 negative pressure, and as shown in FIG. 4, can generate a downforce F that attracts the vehicle body 2 to the ground by the ground effect.

As shown in FIG. 6, a plurality of straightening vanes 15 for partitioning the exhaust port 12 in the width direction (left-right direction in FIG. 6) are provided on the lower surface 14a of the inclined extension portion 14. The straightening vanes 15 are provided on the lower surface 14a of the inclined extending portion 14 at substantially equal intervals in the vertical direction. Therefore, when the undercover 1 is viewed from the downstream end 1b side, the exhaust port 12 is open like a comb. The undercover 1 of the present embodiment has six straightening vanes 15, but the number of straightening vanes 15 is not limited to six.

Each straightening vane 15 extends downward from the lower surface 14a of the inclined extending portion 14 in a plate shape. The lower end portion 15a of each straightening vane 15 is stopped at the position of the lower edge portion 12b of the exhaust port 12. Therefore, the lower end portion 15a of each straightening vane 15 is arranged on the same surface as the lower surface plate 13b of the exhaust flow path portion 13.

In this way, by providing a plurality of rectifying plates 15 for partitioning the exhaust port 12 in the width direction on the lower surface 14a of the inclined extending portion 14, the flow of exhaust gas flowing out from the exhaust port 12 is arranged by the rectifying plate 15. Moreover, according to the undercover 1, the exhaust gas flows through the horizontally long flat and wide internal space 10 in the exhaust flow path portion 13 so as to stick to the bottom surface of the vehicle body 2, and thus is down due to the diffuser effect. Force F can be generated more effectively.

Further, two of the six straightening vanes 15 are arranged at both ends of the exhaust port 12 in the width direction. Therefore, it is possible to prevent the inflow of air from the side into the exhaust port 12. As a result, the undercover 1 can improve the rectifying effect of the exhaust gas by the rectifying plate 15 and further enhance the diffuser effect.

The undercover 1 of the present embodiment is connected to an exhaust portion that discharges the exhaust gas after the inflow port 11 is purified by the exhaust gas purification device of the engine, and is attached to the bottom surface of the vehicle body 2. There is no specific limitation on the structure of the engine, and the undercover 1 can be widely applied as an undercover of a vehicle including a commonly used vehicle engine. However, it is particularly preferable that the undercover 1 of the present embodiment is configured so that the exhaust gas discharged from the engine and recovered from the exhaust heat flows in from the inflow port 11. Since the exhaust gas is recovered at a low temperature by recovering the exhaust heat, the undercover 1 can be a resin product (resin molded product) integrally molded with a resin such as polypropylene, for example. As a result, the weight of the undercover 1 can be reduced, the lower portion of the vehicle body 2 to which the undercover 1 is attached can be reduced in weight, and fuel efficiency and steering stability can be improved.

FIG. 7 is a diagram showing an example of a configuration in which the undercover 1 is connected to an internal combustion engine having an exhaust heat recovery structure.
The thermodynamic cycle system 100 includes the engine 3 as a part of the path, the cooling circuit 101 in which the cooling water circulates, the Rankine cycle circuit 102 in which the insulating organic medium circulates, and the exhaust discharged from the engine 3. It is provided with an exhaust purification device 103 for purifying.

The cooling circuit 101 includes a cooling water circulation flow path 101a in which cooling water that exchanges heat with the engine 3 and its exhaust is circulated, and a heater core 101b that heats the vehicle interior with the cooling water flowing through the circulation flow path 101a. .. The circulation flow path 101a includes the evaporator 102e provided in the Rankin cycle circuit 102 and the heat exchanger 103c provided in the exhaust purification device 103 in the flow path, and is connected to the engine 3 by the cooling water flowing in the circulation flow path 101a. By flowing through the heat exchanger 103c provided in the exhaust purification device 103, the heat exchange between the engine 3 and the exhaust after being purified by the exhaust purification catalyst 103b is promoted. ..

The Rankine cycle circuit 102 includes an annular circulation flow path 102a in which an insulating organic medium having a boiling point and a lower specific heat than that of cooling water circulates, a compression expander 102b provided in the circulation flow path 102a, and a condenser. It includes a 102c, a pump 102d, and an evaporator 102e.

The compression expander 102b is provided between the evaporator 102e and the condenser 102c in the circulation flow path 102a. The compression expander 102b decompresses the organic medium flowing from the evaporator 102e side to the condenser 102c side in the circulation flow path 102a, and compresses the organic medium flowing through the circulation flow path 102a from the condenser 102c side to the evaporator 102e side. The compression expander 102b decompresses the organic medium that has passed through the evaporator 102e and supplies it to the condenser 102c when the organic medium flows in the circulation flow path 102a from the evaporator 102e side to the condenser 102c side in the normal direction. Further, the compression expander 102b compresses the organic medium that has passed through the condenser 102c and supplies it to the evaporator 102e at the time of reversal in which the organic medium flows from the condenser 102c side to the evaporator 102e side in the circulation flow path 102a. A motor generator (not shown) is connected to the drive shaft of the compression expander 102b, and electric energy can be exchanged with and from the battery (not shown).

The condenser 102c is provided on the downstream side of the compression expander 102b along the direction in which the organic medium flows from the evaporator 102e side to the condenser 102c side in the circulation flow path 102a. The condenser 102c includes a fan 102f for supplying outside air, and exchanges heat between the organic medium in the circulation flow path 102a and the outside air.

The evaporator 102e is provided on the upstream side of the compression expander 102b along the direction in which the organic medium flows from the evaporator 102e side to the condenser 102c side in the circulation flow path 102a. The evaporator 102e exchanges heat between the organic medium flowing through the circulation flow path 102a of the Rankine cycle circuit 102 and the cooling water flowing through the circulation flow path 101a of the cooling circuit 101.

The pump 102d is provided on the downstream side of the condenser 102c in the circulation flow path 102a along the direction in which the organic medium flows from the evaporator 102e side to the condenser 102c side. The pump 102d compresses the organic medium flowing through the circulation flow path 102a from the evaporator 102e side to the condenser 102c side.

The exhaust purification device 103 includes an exhaust flow path 103a for exhausting from the engine 3, an exhaust gas purification catalyst 103b provided in the exhaust flow path 103a for purifying the exhaust gas flowing through the exhaust flow path 103a, and an exhaust gas purification device 103a. A heat exchanger 103c provided on the downstream side of the catalyst 103b is provided.

The heat exchanger 103c exchanges heat between the exhaust gas in the exhaust flow path 103a after being purified by the exhaust purification catalyst 103b and the cooling water in the circulation flow path 101a of the cooling circuit 101. As a result, the exhaust gas that has passed through the heat exchanger 103c is recovered as exhaust heat, and the exhaust gas whose temperature has dropped is discharged from the exhaust unit 104. The undercover 1 of the present embodiment is attached to the vehicle body 2 by connecting the inflow port 11 to the discharge portion 104.

The exhaust heat recovery structure of the engine to which the undercover 1 which is a resin product is connected may be any structure as long as it recovers the heat of the exhaust gas from the engine and discharges the exhaust gas whose temperature has dropped, as shown in FIG. Not limited to.

As described above, the undercover 1 according to the present embodiment has the following effects.
The undercover 1 is provided so as to cover the bottom surface of the vehicle body 2, is arranged at the upstream end 1a, has a cylindrical inflow port 11 for inflowing exhaust gas from an internal combustion engine, and a downstream end 1b corresponding to the rear portion 2b of the vehicle body 2. An exhaust flow path portion 13 which is arranged in a flat and wide opening and is connected between the inflow port 11 and the exhaust port 12 and extends in a flat plate shape over a region 20 corresponding to the passenger compartment. , Have. As a result, the undercover 1 functions as an exhaust system component on the bottom surface of the vehicle body, and the exhaust flow path portion 13 from the inflow port 11 to the exhaust port 12 has a flat plate shape, so that the undercover 1 is placed on the bottom surface of the vehicle body 2. Even if it is installed, it does not narrow the passenger compartment space. Further, since the undercover 1 does not project to the bottom surface of the vehicle body 2, the vehicle height can be lowered.

The undercover 1 is a resin product, and the weight of the undercover 1 can be reduced by allowing the exhaust gas discharged from the internal combustion engine 3 to recover the exhaust heat to flow in from the inflow port 11, and the lower part of the vehicle body 2 can be reduced in weight. By reducing the weight of the engine, it is possible to improve fuel efficiency and steering stability.

The upper edge portion 12a of the exhaust port 12 has an inclined extending portion 14 that inclines diagonally upward toward the rear of the exhaust port 12, so that the exhaust gas that has passed through the inside of the exhaust flow path portion 13 can be exhausted from the exhaust port 12. Immediately after being discharged, it spreads diagonally upward, so the air on the bottom side of the vehicle body 2 is vigorously accelerated backwards to make the bottom surface side of the vehicle body 2 negative pressure, and the downforce that attracts the vehicle body 2 to the ground by the ground effect. F can be generated.

By having a plurality of rectifying plates 15 for partitioning the exhaust port 12 in the width direction on the lower surface 14a of the inclined extension portion 14, the flow of the exhaust gas flowing out from the exhaust port 12 is adjusted, so that the downforce F can be more effectively performed. Can be generated.

By arranging two of the plurality of straightening vanes 15 at both ends in the width direction of the exhaust port 12, it is possible to prevent the inflow of air from the side into the exhaust port 12, so that the straightening vane 15 can be prevented. The rectifying effect of the exhaust gas can be enhanced.

1 Undercover 1a Upstream end 1b Downstream end 11 Inflow port 12 Exhaust port 12a Upper edge part 13 Exhaust flow path part 14 Inclined extension part 14a (Inclined extension part) Bottom surface 15 Rectifying plate 2 Car body 2b (Car body) Rear part 3 Internal combustion engine

Claims (5)

It is an undercover provided to cover the bottom of the car body,
A cylindrical inflow port located at the upstream end that allows exhaust gas from the internal combustion engine to flow in,
An exhaust port located at the downstream end corresponding to the rear part of the vehicle body and having a flat and wide opening,
An undercover having an exhaust flow path portion that connects between the inflow port and the exhaust port and extends in a flat plate shape over a region corresponding to the passenger compartment. The undercover is a resin product and is
The undercover according to claim 1, wherein the exhaust gas after being discharged from the internal combustion engine and the exhaust heat is recovered flows in from the inlet. The undercover according to claim 1 or 2, wherein the upper edge portion of the exhaust port has an inclined extending portion that inclines diagonally upward toward the rear of the exhaust port. The undercover according to claim 3, further comprising a plurality of straightening vanes that partition the exhaust port in the width direction on the lower surface of the inclined extension portion. The undercover according to claim 4, wherein two of the plurality of straightening vanes are arranged at both ends in the width direction of the exhaust port.

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